The present invention relates to computer systems and, more particularly, to an improved apparatus and methodology for displaying search results.
The volume of documents in computer databases is rapidly expanding. In spite of this expansion, paper documents are still in wide use. As a result, it is generally useful to be able to convert the paper documents into a form that a computer may use to store or otherwise process the documents. A typical technique for this conversion process is to create a xe2x80x9cdocument image,xe2x80x9d which is typically a bitmap representation of the paper document. This bitmap representation is in digital form. In particular, a bitmap representation is a matrix of digital values wherein each value represents black-and-white, grey scale, or color pixels arranged to form an image of the document. A computer converts the digital values into pixels that are displayed for a user on a display unit, such as a computer monitor. The combined effect of the pixels is to create a document image which is read by the user from the computer monitor.
Although a document image is an appropriate form for representing most, if not all, of the information on a paper document, e.g., words and pictures, this form is not generally appropriate for a computer to perform textual operations. An example of a textual operation is searching for documents that match certain terms or keywords of a query input by a user. A representation for a document which is more conducive for computer-implemented textual operations is a text code. In a text code, each letter of the document is encoded as an entity in a standard encoding format, e.g. ASCII. Since each letter is separately encoded, a search engine, for example, can efficiently examine the textual content of a document and determine whether the document matches a query.
The problem with a text code is that it does not represent non-alphabetic and non-numeric images, such as pictures, in the document. Generally, when a document is converted into a form for use with a computer, it is desirable that both text operations and image display can be performed on the document. Accordingly, some computer systems maintain both a document image and document text for each document stored in the system. The document text is used for textual operations, such as searching a database of document texts for search terms, but the corresponding document image of a matching document is displayed to the user, so that graphical information contained in the matching document is presented to the user as well as the textual information.
One disadvantage of conventional computer systems, however, is that it is difficult for the user to determine from the document image which parts of the document matched the search terms and whether the matching document is relevant to the user.
There exists a need for facilitating the identification of which parts of a document match search terms when displaying an image of a document. There is also a need for making it easier for a user to determine whether a matching document is relevant.
This and other needs are met by the present invention, in which characters in document images from original paper documents are recognized, e.g. through OCR, to produce respective document texts. Regions in the document images that correspond to words in the respective document texts are determined. A matching document, which includes a word matching a search term received as input, from among the document texts is retrieved, e.g. by a search engine. A matching document image corresponding to the matching document text is displayed in a first manner. A featured region in the matching document image that includes a matching region in the matching document image corresponding to the matching word is determined and displayed in a second manner that is visually distinct from the first manner, for example, highlighted in one color.
By displaying in a visually distinctive manner a region of the document image that corresponds to a matching word in the document text, the user can more easily determine which parts of the document matched a search term.
In one embodiment, the featured region is a region of the document image corresponding to the matching word in the document text. In another embodiment, the featured region is a region of the document image corresponding to a noun phrase of consecutive words including the matching words of the document text.
In still another embodiment of the invention, a reference text, which is different from any of the search terms, in the document text is determined. A second featured region in the matching document image that includes regions in the matching document image corresponding to the reference text is determined and displayed in a third manner that is visually distinct from the first manner and the second manner, for example, highlighted in another color. By highlighting reference texts in the document image in a second visually distinctive manner, the user can quickly determine by looking at the search terms and the reference texts how relevant the matching document is.
Additional objects, advantages, and novel features of the present invention will be set forth in part in the detailed description which follows, and in part will be come apparent upon examination or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.